Cannon-pinion for watches.



No. 768,289. PATENTED AUG. 28, 1904.

G. KUBNZEL.

CANNON PINION FOR WATCHES. APPLICATION FILED MAB. 3. 1904.

N0 MODEL.

UNITED STATES Patented August 23, 190 1.

PATENT OFFICE.

CANNON-PINION FOR WATCHES- SPEOIFICATION forming part of Letters PatentNo. 768,289, dated August 23, 1904. Application filed March 3,1904.Serial No. 196,396- (No model.)

To a, whom it may concern.-

Be it known that I, CHRISTOPHER KUENZEL, a citizen of the United Statesof America, and a resident of Springfield, in the county of Hampden andState of Massachusetts, have invented certain new and usefulImprovements in Cannon-Pinion and Center-Post Connections for Vvatches,of which the following is a full, clear, and exact description.

This invention relates to improvements in watches, and more particularlyto the means of engagement between the cannon-pinion and the center postor arbor of the watch, it being requisite, as well known, that thecannon-pinion shall have such an engagement with the post that it willrotate exactly in unison with the latter to carry the hand around in therunning of the watch and yet be capable of a rotary movementindependently of the center post to permit hand-setting.

The object of this invention is to provide means of engagement betweenthe center post and the cannon-pinion, whereby the usual conditions andcapabilities are established, but which is of unusual simplicity,reliability, durability, convenience in the assemblage and detachment ofthe parts, and which contributes in securing accuracy of action evenafter considerable wear has ensued from protracted use.

The invention consists in the combination, with the center post of awatch having a necked portion at its upper extremity with a shouldertherebelow, of a metallic tube split, and thereby rendered expansibleand contractible about said necked portion of the post and the can-'non-pinion, having an axial bore therethrough and having a frictionableengagement about said split metallic tube.

The improvements are fully and clearly illustrated in the accompanyingdrawings, in which- Figure l is a side view of the center post, havingthe detachably-engaged cannon-pinion shown in section in its placethereon. Fig. 2 is a horizontal sectional view as taken on the planeindicated by line 2 2, Fig. 1, and showing parts therebelow in planview. Fig. 3 is a perspective view of the split metallic expansible andcontractible bearing-tube. Fig.

Similar characters of reference indicate corresponding parts in all ofthe views.

In the drawings, A represents the center post or arbor of thewatch-movement, aflixed on which are the center wheel B and the centerpinion (J. The center post has its upper extremity constructed with acylindrical necked down portion 6, below which is the shoulder (Zorseat, and the post has another shoulder g at its upper end. Theintermediate cylindrical portion below the shoulder (Z of the postaffords the journal-bearing for the center post through themovement-plate. D represents the cannon-pinion, which includes theupwardly-extended hub (0, having a cylindrical bore therethrongh ofuniform diameter from end to end, said diameter being such as to enablethe bore of the cannonpinion hub to be passed over the top shoulder g ofthe center portion to encircle and inclose the aforementioned neckeddown portion 71.

G represents a metallic split sleeve or tube, the cleft j beingpreferably parallel with its axis, and this tube is capable of beingexpanded so as to be crowded over the top shoulder g of the post and toreact and become constructed firmly and with a frictional engagementabout the necked down portion 7), this split tube having a length equalto the distance between the shoulders (Z and g, which latter keep itagainst endwise lash relatively to the post, and the external diameterof the split tube is such as to receive the cannonpinion thereabout witha frictional engagement, so that the pinion may be rotated independentlyof the post when the friction is overcome, and in such a case theelastic tube will turn with the pinion and relatively to the post, owingto the fact that the increased external surface of the tube gives agreater frictional surface than is present between the inbase of saidnecked portion, and with a shoulder at its upper end; a cylindrical,expansible split sleeve having a single cleft extending the entirelength thereof, arranged on said necked portion and abutting at itsrespective ends the shoulders on the post, whereby said sleeve ismaintained against displacement from said post, and a cannon-pinionhaving an axial bore surrounding and frictionally engaging with saidsleeve throughout the entire length thereof.

Signed by me at Springfield, Massachusetts, in presence of twosubscribing witnesses.

CHRISTOPHER KUENZEL.

Witnesses:

VVM. S. BELLOWS, A. V. LEAHY.

